Cover for a swimming pool main drain

ABSTRACT

A main drain of a swimming pool has a housing, a removable cover, and one elongated opening formed therein. In one embodiment, the housing is oval in shape with the elongated opening running parallel to the major dimension of the housing to provide a single extended opening that would be difficult for a swimmer to obstruct. In an alternative embodiment, the elongated opening extends over a round cover and is H-shaped. Each elongated opening is formed to have an internally curved flange to provide a smooth edge and structural stiffness for the cover. The single extended opening with its smooth, rounded edges reduces the likelihood of entrapment and entanglement and allows large debris, such as leaves, to pass more easily into the main drain.

CROSS-REFERENCE TO RELATED APPLICATIONS

Not applicable

BACKGROUND OF THE INVENTION

The present invention relates to covers for swimming pool main drains.

A swimming pool has one or more main drains that remove watercontinuously from the bottom of the pool. The removed water issubsequently filtered of both suspended particulate and sediment to keepit both clear and clean before it is returned to the pool. From time totime, larger debris, such as water-soaked leaves, will descend to thebottom of the pool and can be drawn into the drain through its cover forremoval.

However, main drains, because of the relatively powerful suctionrequired for normal operation, pose hazards to swimmers, particularlysmall children. The suction can trap swimmers and sometimes hold them tothe drain, which is commonly located in the deepest part of the pool. Atother times, the configuration of the drain, in combination with thesuction, will entangle the swimmer's hair or clothing. Either of thesecircumstances can be fatal to the swimmer.

Drain covers are frequently designed with many small openings to avoidthe aforementioned problems. However, they will then not be suitable fordraining larger debris and may still cause entrapment and entanglement.

A drain cover needs to have a total opening area sufficient to allow thepool to drain and to admit leaves and other larger debris, but avoid orat least reduce the possibility of the entrapment and entanglement ofswimmers.

SUMMARY OF THE INVENTION

Briefly recited and according to its major aspects, the presentinvention is a main drain cover for a swimming pool. The particularfeature of the present invention is its utilitarian shape, which ischaracterized by a gently domed overall shape and a single, extendedopening with rounded edges. The present invention may also include anadaptor collar, to fit the cover to the main drain housing, and thehousing itself.

In two of the embodiments described herein, the pool is drained througha single extended opening characterized by smooth, curved edges. Thefirst of these is a straight, elongated opening; the second is shapedroughly like the letter “H.” The size and extent of the openings is animportant feature of the present invention. Because of their size andextent, the openings are relatively more difficult for a swimmer toblock than more compact openings would be. Because of their smoothlyrounded edges, free of corners and projections, they are much lesslikely to entangle the hair or clothing of swimmers. Furthermore, largerdebris will be more easily drawn in through the larger, roundedopenings.

An advantage of the second embodiment of the present invention is thatthe cover can be used on both new and previously existing drain housingsand on housings with two and with three ports, such as those withentrapment relief ports in addition to suction ports and hydrostaticrelief ports.

Other features and their advantages will be apparent to those skilled inthe art of swimming pool water circulation system design from a carefulreading of the Detailed Description of Preferred Embodiments accompaniedby the following drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

In the drawings,

FIG. 1 is top view of a cover for a main drain of a swimming pool,according to a first preferred embodiment of the present invention;

FIG. 2 is a side, cross sectional view of the main drain of FIG. 1,taken along lines 2-2;

FIG. 3 is a top view of a cover for a main drain of a swimming pool,according to a second preferred embodiment of the present invention

FIG. 4 is a side, cross sectional view of the main drain of FIG. 3,taken along lines 4-4; and

FIG. 5 is a detailed, cross sectional view of the main drain of FIG. 3,taken along lines 5-5.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

The present invention is a device for covering a swimming pool maindrain; a main drain with a cover; and a cover and adaptor collar forcovering a main drain. While specifically intended for use in swimmingpools, the present drains could be used for a drain of a body of waterin a tank or reservoir where entrapment, entanglement, or draining oflarger debris is a concern. Two embodiments of the present main draincover are presented in the figures and will be described below.

Referring now to the FIGS. 1 and 2, there is illustrated a main drain 10according to a first preferred embodiment of the present invention, andgenerally indicated by reference number 10. Main drain 10 is made of amaterial such as polyvinyl chloride that is substantially resistant tothe environment of a swimming pool and to the typical chemicals used formaintaining the pool water free of bacteria and mold.

Main drain 10 comprises a cover 12 and a housing 14 that are joinedtogether in a way that allows cover to be removed periodically forcleaning the interior of housing 14, such as by a friction fit betweenthe walls 16 of housing 14 and depending flanges 18 of cover 12.Alternatively, cover 12 and housing 14 can be formed with threads.

Housing 14 has a major dimension and a minor dimension with the formerbeing longer than the latter by typically a factor of two. Housing 14also has a hydrostatic relief port 26 and a bottom suction port 28.Bottom suction port 28 allows water and heavier debris to be sucked fromthe interior of a swimming pool from a region adjacent main drain 10through main drain 10 and thence to a canister filter (not shown).Hydrostatic relief port 26 allows water that may have accumulated undera pool to be removed. Typically bottom suction port 28 has a 2½-inchdiameter opening; hydrostatic relief port 26 has a 2-inch opening. Somedrain housings have an additional port, as will be described below inconnection with the embodiment shown in FIGS. 3-5 but which may beincorporated into first embodiment if desired. Thus, the embodiment ofcover 12 shown in FIGS. 1 and 2 can be used in connection with atwo-port housing as shown or with a three-port housing as describedbelow in connection with the second embodiment of the present invention.In the Embodiment with a two-port housing, the drains should always beinstalled in pairs connected to the suction source by a tee or a X tofurther defeat entrapment.

Running parallel to the major dimension is a narrow, linear opening 40.Opening 40 has an internally curved flange 42 that runs the length ofopening 40. While flange 42 adds stiffness, its primary purpose is toavoid sharp edges that may injure those whose fingers are inserted intoopening 40 and to avoid entanglement. Opening 40 is preferably the widthof a large human finger so that children's fingers are unlikely tobecome stuck fast. Furthermore, larger debris such as leaves can enteropening 40 when sucked into main drain 10 more easily than they canenter many smaller openings.

In an alternate preferred embodiment, shown in FIGS. 3, 4 and 5, anothermain drain 50 is shown. Main drain 50 has a cover 52 and a housing 54.Cover 52 is not joined directly to housing 54 but is coupled to it usinga collar 56 that allows cover 52 to be adaptably connected to variouspre-existing housings 54 having different dimensions. Rather than onelong, linear opening as illustrated in FIGS. 1 and 2, an H-shapedopening 60 permits the entrance of pool water and debris. Opening 60 isan internally curved surface 64 (best seen in FIGS. 4 and 5) to provideboth structural stiffening while reducing the likelihood of entanglementand entrapment.

As with main drain 10, main drain 50 has a hydrostatic relief port 66and a bottom suction port 68. In addition, as best seen in FIGS. 4 and5, main drain 50 has an entrapment relief port 70 that typically isconnected to a line that runs to a different part of the pool such as awall. In the event opening 60 is blocked, suction from bottom suctionport 68 would be relieved through entrapment relief port 70. As statedabove, cover 52 may be used on a two-port housing of the type shown inFIGS. 1 and 2, or the three-port housing 54 as shown in FIGS. 3-5. Whilethe three-port housing if FIGS. 3-5 is preferred over the two porthousing of FIGS. 1 and 2, a cover either of the type shown in FIGS. 1and 2 or of that shown in FIGS. 3-5 is even more important in a two-porthousing where there is no additional relief port if the opening of thecover is blocked. The extensive shapes of the openings of covers 12, 52,disclosed are more difficult to completely block than less extensiveopenings.

Collar 56 has a lateral flange 74 is secured to pool surface 76 byfriction fit as shown and perhaps also with screws 58 while supportingan upstanding flange 78 and a depending flange 80. Cover 52 has adepending flange 82 that is friction fitted to upstanding flange 78 ofcollar 56, while depending flange 80 of collar 56 is friction fitted tothe interior of housing 54. Depending flange 80 can be formed on collar56 a little more radially inward or outward depending on thecircumference of the particular size of housing 54 so that dependingflange 80 and housing 54 properly engage.

Both embodiments shown are characterized by a cover 12, 52 having asingle opening 40, 60 that is extended, covering either much of cover12, 52, so that it is less likely that a swimmer will block, eitheraccidentally or intentionally, every part of opening 40, 60, and thuscut off the flow into drain 10, 50. Opening 40, 60 of cover 12, 52 iscurved, rounded, and smooth, free of corners or sharp angles that wouldtend to trap and entangle hair along the opening.

It will be readily apparent to those skilled in the art of swimming poolcirculation system design that many changes and substitutions can bemade to the foregoing preferred embodiments without departing from thespirit and scope of the present invention, defined by the appendedclaims.

1. A main drain for a swimming pool, said main drain comprising: ahousing having a bottom suction port; a cover removably attached to saidhousing, said main drain having a single extended opening formed thereinto allow a flow of water to pass into said housing and through saidbottom suction port, said single extended opening having an inwardlycurved flange running the length of said single extended opening.
 2. Themain drain as recited in claim 1, wherein said housing has a majordimension and a minor dimension and said single extended opening runsparallel to said major dimension.
 3. The main drain as recited in claim2, wherein said major dimension is approximately twice the size of saidminor dimension
 4. The main drain as recited in claim 1, wherein saidhousing is oval in shape.
 5. The main drain as recited in claim 1,wherein said single extended opening is H-shaped.
 6. The main drain asrecited in claim 1, wherein said housing includes an entrapment reliefport.
 7. A main drain for use with a swimming pool, said main draincomprising: a housing with a suction port and an entrapment relief port;a cover for covering said housing, said covering having a single,H-shaped opening formed therein.
 8. The main drain as recited in claim7, wherein said covering is smooth, rounded and curved along saidH-shaped opening.
 9. The main drain as recited in claim 7, wherein saidcover has an internally curved surface.